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A wealth of near infrared spectroscopic data for a large number of galactic objects was recorded with AKARI during its active lifetime. The hydrocarbon emission features around 3.3 – 3.5 m are modelled here as a series of 6 Voigt profiles arising due to hydrogen atoms found in different molecular structures within the emitting spectroscopic carriers. This model is compared and contrasted with a model consisting of 3 Gaussian profiles and found to produce a superior fit to AKARI data. Analysis of the 6 Voigt model shows that the 3.3 m aromatic hydrocarbon band is well described by two components at 3.28 m and 3.30 m . We confirm that the 3.28 μ m band is due to emission from aromatic molecules, and find a good correlation between the 3.28 μ m and 3.41 m bands, assigned to bay-hydrogen sites and linking methylene groups respectively. Results are discussed in terms of molecular processing and dust formation. [ABSTRACT FROM AUTHOR]

In avian species, primordial germ cells (PGC) use the vascular system as a vehicle to transport them to the future gonadal region. The aim of this study was to elucidate the details of migration system and size of the PGC population in the early chicken embryo. We analyzed whole chicken embryos during stages X and 2 to 17 by immunohistochemical staining using specific antibody raised against chicken vasa homolog. At stage X, PGC were dense in the central zone of the area pellucida. Following the formation of the primitive streak, PGC moved anteriorly to the edge of the extraembryonic region. The size of the PGC population increased gradually during stages X (130.4 ± 31.9) to 10 (439.3 ± 93.6). At stage 10, PGC began to accumulate in the region anterior to the head, and then we could observe that PGC invaded into the vascular system in this region. At stage 11, the number of PGC decreased in the region anterior to the head (129.8 ± 42.5 to 46.7 ± 4.2) and increased in the blood vessels (194.0 ± 41.6 to 285.0 ± 7.5). No PGC could be recognized in the intermediate mesoderm, the future gonadal region, until stage 14, but they first appeared there at stage 15. The number of PGC recognized in the intermediate mesoderm increased from stage 15 to 17. Interestingly, the number of PGC between the left and right sides of this region was consistently and significantly different (P < 0.05) in females and males. The present study mainly clarified that chicken PGC continue to proliferate throughout early development, many PGC invaded into the vascular system from the region anterior to the head in stage 11, and PGC actively left the blood vessels and migrated to the intermediate mesoderm from stage 15. [ABSTRACT FROM AUTHOR]

Abstract: Cometary dust trails were first observed by IRAS; they are widely known to be the origins of meteoric showers. A new window has been opened for the study of dust trails, using ground-based observations. We succeeded in obtaining direct images of the 22P/Kopff dust trail with the Kiso 1.05-m Schmidt telescope. Following this initial success, we have continued to perform a dust trail survey at Kiso. As a result of this survey, we have detected dust trails along the orbit of six periodic comets, between February 2002 and March 2004. The optical depth of these dust trails are 10−9 to 10−8, which is consistent with IRAS measurements. In this paper, we describe the observations and data reduction procedures, and report the brief result obtained between February 2002 and March 2004. [Copyright &y& Elsevier]